1. Field of the Invention
This invention relates to RF MEMS microwave switches, a switch matrix and a method of fabricating a monolithic switch. More particularly, this invention relates to a multi-port RF MEMS switch having a monolithic structure with clamped-clamped beams, cantilever beams or thermally operated actuators.
2. Description of the Prior Art
Satellite beam linking systems vastly rely on switch matrix functionality to manage traffic routing and for optimum utilization of system bandwidth to enhance satellite capacity. A beam link system creates sub-channels for each uplink beam where the switch matrix provides the flexibility to independently direct the beams to the desired downlink channel. Switch matrices can also provide system redundancy for both receive and transmit subsystems and improve the reliability of the systems. In case of failure of any amplifiers, the switch matrix reroutes the signal to the spare amplifier and thus the entire system remains fully functional.
The two types of switches that can be currently used in the form of switch matrices are mechanical switches and solid state switches. Mechanical (coaxial and waveguide) switches show good RF performance up to couple of hundred gigahertz. However, mechanical switches are heavy and bulky as they employ motors for the actuation mechanism. This issue is more pronounced in the form of switch matrices where hundreds of multi-port switches are integrated together. Solid state switches, on the other hand, are relatively small in size, but they show poor RF performance especially in high frequency applications (100-200 GHz) and they have DC power consumption.